[codex] reuse chats and sources more effectively

[Abdulmuiz44]

Summary

This branch adds a stronger retention loop for Tera:

• research answers now expose source citations directly in chat
• the profile page now manages project memory, saved workflows, and export/search entry points
• the history page now lets users turn real conversations into reusable workflows

Why

The fastest way to increase usage is to make Tera easier to return to and easier to reuse. Users should be able to:

• trust research answers with visible sources
• save useful context instead of retyping it
• turn prior prompts into repeatable workflows
• export or search their own workspace data when they need it

What changed

• Added citation metadata to research responses and rendered those sources in the chat UI.
• Added project memory management backed by user_memories.
• Added saved workflows with local persistence, search, export, and launch-in-chat links.
• Added profile quick actions for history, notes, uploads, and JSON export.
• Added workflow capture from history items so real chats become reusable templates.

Validation

• Ran git diff --check successfully.
• Ran a repository type-check attempt earlier in the session; the remaining failures were unrelated pre-existing blockchain-lab route typing issues.